998 resultados para Análise de flutuação sem tendências


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Nicholas Kaldor is known as an author who often changed his mind throughout his career. This is the case of his analyses of the process of economic growth, in which he proposed various models leading to quite different and, occasionally, conflicting conclusions. Specifically, Kaldor changed his position concerning the stability of the full employment situation. This paper shows that, in spite of those changes, Kaldor in fact used different versions of the same basic analytical framework and that this framework has its origin in his paper "Stability and Full Employment" published in the Economic Journal in December 1938.

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The main objective of this study is to apply recently developed methods of physical-statistic to time series analysis, particularly in electrical induction s profiles of oil wells data, to study the petrophysical similarity of those wells in a spatial distribution. For this, we used the DFA method in order to know if we can or not use this technique to characterize spatially the fields. After obtain the DFA values for all wells, we applied clustering analysis. To do these tests we used the non-hierarchical method called K-means. Usually based on the Euclidean distance, the K-means consists in dividing the elements of a data matrix N in k groups, so that the similarities among elements belonging to different groups are the smallest possible. In order to test if a dataset generated by the K-means method or randomly generated datasets form spatial patterns, we created the parameter Ω (index of neighborhood). High values of Ω reveals more aggregated data and low values of Ω show scattered data or data without spatial correlation. Thus we concluded that data from the DFA of 54 wells are grouped and can be used to characterize spatial fields. Applying contour level technique we confirm the results obtained by the K-means, confirming that DFA is effective to perform spatial analysis

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The main objective of this study is to apply recently developed methods of physical-statistic to time series analysis, particularly in electrical induction s profiles of oil wells data, to study the petrophysical similarity of those wells in a spatial distribution. For this, we used the DFA method in order to know if we can or not use this technique to characterize spatially the fields. After obtain the DFA values for all wells, we applied clustering analysis. To do these tests we used the non-hierarchical method called K-means. Usually based on the Euclidean distance, the K-means consists in dividing the elements of a data matrix N in k groups, so that the similarities among elements belonging to different groups are the smallest possible. In order to test if a dataset generated by the K-means method or randomly generated datasets form spatial patterns, we created the parameter Ω (index of neighborhood). High values of Ω reveals more aggregated data and low values of Ω show scattered data or data without spatial correlation. Thus we concluded that data from the DFA of 54 wells are grouped and can be used to characterize spatial fields. Applying contour level technique we confirm the results obtained by the K-means, confirming that DFA is effective to perform spatial analysis

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O objetivo deste trabalho foi usar a análise estatística para identificar tendências anuais da temperatura e precipitação pluvial. Foi usada a série histórica de 1924 a 1998 de precipitação pluvial e temperatura média do ar à superfície, da estação meteorológica de Urussanga (latitude 28º31' S, longitude 49º19' W e altitude de 48,2 m). Foram empregados a análise de regressão e os testes paramétricos de Run, Mann-Kendall e Pettitt. Os resultados indicam que houve tendência significativa no aumento da temperatura média anual e na temperatura média do mês de janeiro, sendo que a mudança ocorreu no ano de 1965. Não foi identificada nenhuma tendência significativa na temperatura média do mês de julho. Também foi identificada a tendência significativa de aumento da precipitação pluvial total anual, e da precipitação pluvial total no quarto trimestre. Nos três primeiros trimestres do ano, nenhuma tendência significativa foi identificada.

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This work aims to study the fluctuation structure of physical properties of oil well profiles. It was used as technique the analysis of fluctuations without trend (Detrended Fluctuation Analysis - DFA). It has been made part of the study 54 oil wells in the Campo de Namorado located in the Campos Basin in Rio de Janeiro. We studied five sections, namely: sonic, density, porosity, resistivity and gamma rays. For most of the profiles , DFA analysis was available in the literature, though the sonic perfile was estimated with the aid of a standard algorithm. The comparison between the exponents of DFA of the five profiles was performed using linear correlation of variables, so we had 10 comparisons of profiles. Our null hypothesis is that the values of DFA for the various physical properties are independent. The main result indicates that no refutation of the null hypothesis. That is, the fluctuations observed by DFA in the profiles do not have a universal character, that is, in general the quantities display a floating structure of their own. From the ten correlations studied only the profiles of density and sonic one showed a significant correlation (p> 0.05). Finally these results indicate that one should use the data from DFA with caution, because, in general, based on geological analysis DFA different profiles can lead to disparate conclusions

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The study of complex systems has become a prestigious area of science, although relatively young . Its importance was demonstrated by the diversity of applications that several studies have already provided to various fields such as biology , economics and Climatology . In physics , the approach of complex systems is creating paradigms that influence markedly the new methods , bringing to Statistical Physics problems macroscopic level no longer restricted to classical studies such as those of thermodynamics . The present work aims to make a comparison and verification of statistical data on clusters of profiles Sonic ( DT ) , Gamma Ray ( GR ) , induction ( ILD ) , neutron ( NPHI ) and density ( RHOB ) to be physical measured quantities during exploratory drilling of fundamental importance to locate , identify and characterize oil reservoirs . Software were used : Statistica , Matlab R2006a , Origin 6.1 and Fortran for comparison and verification of the data profiles of oil wells ceded the field Namorado School by ANP ( National Petroleum Agency ) . It was possible to demonstrate the importance of the DFA method and that it proved quite satisfactory in that work, coming to the conclusion that the data H ( Hurst exponent ) produce spatial data with greater congestion . Therefore , we find that it is possible to find spatial pattern using the Hurst coefficient . The profiles of 56 wells have confirmed the existence of spatial patterns of Hurst exponents , ie parameter B. The profile does not directly assessed catalogs verification of geological lithology , but reveals a non-random spatial distribution

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This work aims to study the fluctuation structure of physical properties of oil well profiles. It was used as technique the analysis of fluctuations without trend (Detrended Fluctuation Analysis - DFA). It has been made part of the study 54 oil wells in the Campo de Namorado located in the Campos Basin in Rio de Janeiro. We studied five sections, namely: sonic, density, porosity, resistivity and gamma rays. For most of the profiles , DFA analysis was available in the literature, though the sonic perfile was estimated with the aid of a standard algorithm. The comparison between the exponents of DFA of the five profiles was performed using linear correlation of variables, so we had 10 comparisons of profiles. Our null hypothesis is that the values of DFA for the various physical properties are independent. The main result indicates that no refutation of the null hypothesis. That is, the fluctuations observed by DFA in the profiles do not have a universal character, that is, in general the quantities display a floating structure of their own. From the ten correlations studied only the profiles of density and sonic one showed a significant correlation (p> 0.05). Finally these results indicate that one should use the data from DFA with caution, because, in general, based on geological analysis DFA different profiles can lead to disparate conclusions

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The study of complex systems has become a prestigious area of science, although relatively young . Its importance was demonstrated by the diversity of applications that several studies have already provided to various fields such as biology , economics and Climatology . In physics , the approach of complex systems is creating paradigms that influence markedly the new methods , bringing to Statistical Physics problems macroscopic level no longer restricted to classical studies such as those of thermodynamics . The present work aims to make a comparison and verification of statistical data on clusters of profiles Sonic ( DT ) , Gamma Ray ( GR ) , induction ( ILD ) , neutron ( NPHI ) and density ( RHOB ) to be physical measured quantities during exploratory drilling of fundamental importance to locate , identify and characterize oil reservoirs . Software were used : Statistica , Matlab R2006a , Origin 6.1 and Fortran for comparison and verification of the data profiles of oil wells ceded the field Namorado School by ANP ( National Petroleum Agency ) . It was possible to demonstrate the importance of the DFA method and that it proved quite satisfactory in that work, coming to the conclusion that the data H ( Hurst exponent ) produce spatial data with greater congestion . Therefore , we find that it is possible to find spatial pattern using the Hurst coefficient . The profiles of 56 wells have confirmed the existence of spatial patterns of Hurst exponents , ie parameter B. The profile does not directly assessed catalogs verification of geological lithology , but reveals a non-random spatial distribution

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Dissertação para obtenção do Grau de Mestre em Engenharia do Ambiente, perfil Gestão e Sistemas Ambientais

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FUNDAMENTO: A variabilidade da frequência cardíaca (VFC) é um importante indicador da modulação autonômica da função cardiovascular. A diabetes pode alterar a modulação autonômica danificando as entradas aferentes, dessa forma aumentando o risco de doenças cardiovasculares. Foram aplicados métodos analíticos não lineares para identificar os parâmetros associados com VFC indicativos de alterações na modulação autonômica da função cardíaca em pacientes diabéticos. OBJETIVO: Analisamos as diferenças nos padrões da VFC entre pacientes diabéticos e controles saudáveis pareados por idade, utilizando métodos não-lineares. MÉTODOS: Plot de Poincaré Lagged, autocorrelação e análise de flutuação destendenciada foram aplicados para analisar a VFC em registros de eletrocardiograma (ECG). RESULTADOS: A análise do gráfico de Poincaré lagged revelou alterações significativas em alguns parâmetros, sugestivas de diminuição da modulação parassimpática. O expoente de flutuação destendencionada derivado de um ajuste em longo prazo foi maior que o expoente em curto prazo na população diabética, o que também foi consistente com a diminuição do input parassimpático. A função de autocorrelação do desvio dos intervalos inter-batimento exibiu um padrão altamente correlacionado no grupo de diabéticos em comparação com o grupo controle. CONCLUSÃO: O padrão de VFC difere significativamente entre pacientes diabéticos e indivíduos saudáveis. Os três métodos estatísticos utilizados no estudo podem ser úteis para detectar o início e a extensão da neuropatia autonômica em pacientes diabéticos.

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In this dissertation, based on two theoretical frameworks, American functionalism and variationist sociolinguistics, I take as subject the sequence connectors E and AÍ, which has the grammatical function of indicating retroactive-propeller sequenciation of information. I analyze the variable use of these connectors in texts written by students from two public schools in the city of Natal, RN, attending at the time of data collection (the year 2012), two distinct levels of basic education: the sixth and the ninth year. The students who contributed to this research wrote, as part of their activities in the classroom, texts of two narrative genres: narrative of personal experience (non-fictional) and short story (fictional). In addition, these students and their Portuguese teachers answered a test of linguistic attitude in which they gave their opinions regarding the appropriateness of the use of connectors E and AÍ in contexts of speech and writing marked by distinct degrees of formality. The results obtained by means of quantitative analysis showed different tendencies of linguistic, social and stylistic distribution of connectors E and AÍ in the narrative texts written by the students. I related these results to the action of two principles: the principle of persistence, linked to the process of change by grammaticalization, and the principle of stylistic markedness. Besides, I took into account the answers provided by students and teachers to the test of linguistic attitude for refine the interpretation of the results

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Pós-graduação em Ciências Cartográficas - FCT

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Este trabalho discute o uso da análise de frequência de moscas das famílias Calliphoridae e Muscidae na avaliação do impacto da implantação de programas de coleta seletiva de lixo urbano. Para isto, utilizou-se do estudo de caso de Tupã, município paulista, em duas fases distintas: fase 1 - compreendida entre os meses de junho e outubro de 2001, período caracterizado pela presença do lixão e; fase 2 - entre os meses de novembro de 2001 a maio de 2002, caracterizada pelo início da implantação do processo de coleta seletiva e reciclagem e aterramento gradativo do lixão. Procedeu-se a captura dos insetos com dez armadilhas confeccionadas com garrafas plásticas, de dois litros, do tipo PET, alocadas em residências e árvores ao redor do lixão. Como atrativo utilizou-se aproximadamente 400 ml de vinhaça de cana de açúcar, substituída semanalmente no ato da colheita. Nas duas fases da pesquisa, observou-se que a família mais frequente e constante foi a Calliphoridae.  Houve correlação positiva, antes da coleta seletiva, entre o número de califorídeos e a precipitação pluviométrica (0,638) e, entre o número de muscídeos e a temperatura média (0,605). Após a coleta, o mesmo não foi observado. O programa de coleta seletiva implantado nesse município paulista resultou em diminuição significativa na frequência de dípteros e a análise da flutuação de califorídeos e muscídeos demonstrou-se como um eficiente indicador de monitoramento da qualidade ambiental.

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Tese (doutorado)—Universidade de Brasília, Faculdade de Comunicação, Programa de Pós-Graduação em Comunicação, 2016.